Heating oven



Sept. 7, 1954 w. J. MISKELLA HEATING OVEN 3 Sheets-Sheet 1 Filed March 15, 1951 WEI kl gsfi gtzm p 7, 1954 w. J. MISKELLA 2,688,684

HEATING OVEN Filed March 15, 1951 3 Sheets-Sheet 2 P 7, 1954 w. J. MISKELLA 2,688,684

HEATING OVEN I Filed March 15; 1951 3 Sheets-Sheet 3 1 B 2g E :i: I

Patented Sept. 7, 1954 UNITED STATES PATENT OFFICE 4 Claims.

The present invention relates to heating ovens, and particularly to heating ovens of the infrared type.

One of the principal objects of the present invention is to provide a new and improved heating oven which is made up of a plurality of standard units of simple construction.

A further object is to provide a new and improved heating oven made of a plurality of standard units, each of which is of extremely simple and economical construction, being formed primarily of sheet metal.

A still further object is to provide a novel heating oven made up of a plurality of standard units hingedly interconnected so that the oven might enclose a tortuous path conveyor system.

Still another object is to provide a new and improved enclosed heating oven adaptable to a conveyor system and in which heat loss is minimized and in which there need be no break in the source of infrared radiation even though the conveyor system wind back and forth.

A still further object is to provide a heating oven possessing all of the aforementioned advantages, which is flexible in its application, readily assembled, and capable .of being manufactured at low cost.

Other objects and advantages will become apparent from the following description taken in conjunction with the accompanying drawings, wherein:

Fig. 1 is a perspective view of one form of heating oven looking into the interior of the oven from one end;

Fig. 2 is an enlarged fragmentary plan view, with some parts broken into sections, of the heating oven of the present invention;

Fig. 3 is a fragmentary elevational view of the inner face of a bank of heating elements constructed in accordance with the present invention; and

Fig. 4 is an enlarged detail sectional view of the hinge structure.

The heating oven of my invention is made up of a pair of similar banks 28 and 22 of heat radiating elements, each of the banks being supported upon a supporting structure 24 and arranged on either side of a conventional I-beam conveyor rail 26.

Each bank 20, 22 is comprised of a plurality of substantially identically formed units 28 hingedly interconnected about vertically extending pintles or rods 38 which form a part of the supporting structure 24. Each rod 38 slidably extends into a standard size pipe 32 which has its lower end screwed into a flanged fitting 34 which serves as a foot and may be secured to the floor. If desired, the rod 30 may extend all the way to the bottom of the pipe 32, but it will be observed in Figs. 1 and 3 that each of the rods 38 extends appreciably above the upper portion of the oven for a purpose which will appear immediately hereinafter. If the rod 38 does not extend to the bottom of the pipe 32 it is provided with a collar 36 locked in position by a set screw 38 which locates the rod 38 accurately with respect to the pipe 32. As seen most clearly in Fig. 3, the lower edge of each unit 28 rests either on the upper edge of the collar 36 or on the upper edge of the pipe 32 and is, therefore, supported thereby. No appreciable load need be carried by the rod 38.

At the top of the oven the rods 38 are interconnected in pairs by cross rods 48, the cross rods 40 passing through one-half of a double collar fitting 42, the other half of which extends over and embraces a rod 38. Suitable set screws 10- cate the fittings 42 on the rods 38 and 48 so that the two banks of the oven are properly spaced and supported relative to each other and to the conveyor rail 26.

The intervening space between the oven banks 28, 22 is closed at the top of the oven by a radiant ray reflecting cover plate 44 suspended from the rods 48 by means of hangers 46, and the space is closed at the bottom by an oven floor 48 preferably having a reflective inner surface and which is supported on the pipe structure 32. Suitable doors 58 close the entrance and exit from the oven and are hinged to the end pairs of the rods 38. It is to be understood that the panels 44 and 48 and doors 58 may be omitted, and that the oven not necessarily comprise facing banks but any arrangement of lamped banks may be set up as desired according to the demands of the work which is being subjected to infrared radiation.

Each of the oven units 28 comprises a pair of concave sheet metal plates 52, 54, the plate 52 lying within the concave confines of the plate 54, with the space formed therebetween providing a conduit for the electrical wirin for the infrared lamps. Each of the plates 52 has a flat central portion 56 bounded by a pair of obliquely disposed portions 58 which are integral with flange portions 68, the flange portions 68 being parallel to but not coplanar with the central portion 56. Suitable sockets 62 may be bolted to the oblique portions 58, or if desired, they may be secured to the portions 56. However, it is preferred that they be bolted to the oblique portions 58 in order that the infrared rays emanating from infrared bulbs 64 be directed diagonally across the oven toward the opposite oven wall or bank of lamped units in order that all portions of the work being subjected to radiation be contacted by the rays. This arrangement insures that work of irregular shape be struck either by direct rays from the lamps 64 or by rays reflected from the opposite oven wall. The oblique surfaces 58 cause the reflected rays to travel at a variety of angles toward the work. There are, of course, instances where such an arrangement is not desired and in those instances the sockets 62 would be mounted in the central portion 55 of the unit. Under some circumstances, where it is not necessary or desirable that the entire bank of the oven be provided with heat radiatin elements, a plain or unlamped unit may be substituted for a lamped unit. Such units are constructed in the same manner as are the lamped units but are not equipped with lamp sockets 62.

The inwardly directed face of the plate 52 is preferably provided with a reflective surface which may be polished stainless steel, polished aluminum, chromium or cadmium plated porcelain enamel, or any similar surface which has good radiation reflecting characteristics.

The sheet metal plate M is shaped similarly to the plate 52 except that it has directly inwardly extending portions 66 connected to the oblique portions and terminating in flanges 68 which lie behind the flanges S9. The flanges 60 and 68 have sandwiched therebetween the flange m of a strap hinge II, the bearing portions 12 of which are formed immediately adjacent the flange and behind the plane of the flange til so as not to interfere with the unbroken surface of the bank of lamped units. A bolt 74 with its nut i6 and a lock washer l8 secure the plate flanges 60 and 68 and the hinge flange H3 together.

It will be observed from Fig. 3 that each of the lamped units 28 is formed so that the hinge bearing parts l2 may be intermeshed regardless of the manner in which the units 28 are set into the oven, there being a hinge bearing portion 12, a space, another portion 12, etc., throughout the entire length of one side of the unit 28, the opposite edge of the unit bein formed in a complementary manner. Each of the door elements 50 is similarly formed so as to be readily incorporated into an oven structure.

In dot-dash lines in Fig. 2 it is shown that the units 28 can be pivoted about the rods or pintl'es 3t relative to adjacent units 28'. The extent of the movement is such as to form a right angle at the inner face of the unit between any pair of adjacent units. With this hinge interconnection between units 28 an oven may be constructed of a plurality of such units and adapted extremely readily to any conveyor system even though that conveyor follow a somewhat tortuous or winding path.

It will also be observed that a unit constructed as shown and described is extremely simple, having a minimum number of parts many of which" may be purchased from now existing supply sources. By way of example, these parts include the pipe 32, rods 3! foot flanges 3 1, sockets 52, etc. Those parts which are not available on the open market are very readily fabricated from sheet metal with a minimum amount of effort and cost. The assembly of the elements of each unit is is easily and economically accomplished,

and the building of an oven from a plurality of units regardless of the size or heat output demanded from that oven is a relatively simple matter. The particular lamped unit 28 shown in Fig. l is provided with eight lamps, four on each oblique plane 58. This is merely exemplary of a typical unit and any number of lamps can be used. When the unit has the lamp arranged on the oblique portions 58 it is preferable for symmetry and simplicity of oven construction that there be an even number of lamps. Furthermore, the oven bank can be constructed with units in vertical tiers by stacking them on top of each other.

Each bank 20, 22 is usually equipped with a master control 8!] which may be manually adapted to regulate the heat output of the oven. A main conduit 82 connects the master control box with the conduit space in each unit 28. If desired each unit 28 may be equipped with a switch (not shown) by means of which the unit circuit may be connected to or disconnected from the oven supply circuit.

Figs. 1 and 3 show that each oven bank 20, 22 has a substantially solid face to reflect infrared rays directed at it. As a result little infrared radiation is lost by failure to reflect as is the case with ovens of the type constructed of a plurality of individual lamp reflectors.

From the foregoing it is clear that the objectives which were claimed for the heating oven of this invention are attained. Since certain modifications and changes may be made in the oven without departing from the spirit and scope of the present invention, it is intended to be limited only by the appended claims.

What is new and desired to be secured by United States Letters Patent is:

l. A heating oven comprising in combination a pair of banks of infrared radiation sources, each bank comprising a plurality of source supporting units, each unit including a pair of concave plates, one of said plates being nested within the other of said plates with their respective central portions spaced to form a duct therebetween, means securing said plates together along opposite marginal edges, and hinge bearing forming means connected to said plates along said marginal edges by said securing means, said hinge bearing means being formed of sheet metal and being so arranged and spaced that bearing means on adjacent units intermesh and the intermeshed bearing means substantially close the vertical spaces between adjacent units, hinge rods passing through the hinge bearing means of adjacent units, and tubular base means receiving and supporting the lower ends of said hinge rods, and means connected to said hinge rods at their upper ends spacing and interconnecting said banks of infrared radiation sources.

2. A heating oven comprising in combination a pair of banks of infrared lamps, each bank comprising a plurality of sheet metal units ineluding a pair of concave plates, one of said platesbeing nested within the other of said plates with their respective central portions spaced to form a duct therebetween, means securing said plates together along opposite marginal edges, and hinge bearing forming means connected to said plates along said marginal edges by said securing means, hinge rods passing through the hinge bearings of adjacent units, and base means supporting said hinge rods, and means connected to said hinge rods spacing and interconnecting said banks of infrared lamps.

3. In a heating oven a plurality of substantially identical units on which infrared lamps may be mounted, each unit including a pair of concave plates each having a flat central portion and flat side portions arranged at an oblique angle to said central portion, one of said plates being nested within the other of said plates with their respective central portions spaced to form a duct therebetween, a plurality of lamp sockets mounted on the one plate on the inner faces of said side portions, means securing said plates together along opposite marginal edges, and hinge bearing forming means connected to said plates along said marginal edges by said securing means, hinge rods passing alternately through the hinge bearings of adjacent units, and means supporting said hinge rods and said units.

4. A unit for use in constructing a heating oven comprising in combination a pair of longitudinally concave plates each having a flat central portion and flat side portions arranged at an oblique angle to said central portion, one of said plates being nested within the other of said plates with their respective central portions spaced to form a duct therebetween, a plurality of lamp sockets mounted on the one plate on the inner faces of said side portions, means securing said plates together along opposite longitudinal marginal edges, and hinge bearing forming means connected to said plates along said marginal edges by said securing means.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1.580,090 Shoenberg Apr. 6, 1926 2,119,680 Long June 7, 1938 2,418,283 Wilson Apr. 1, 1947 2,441,831 Moore May 18, 1948 2,458,184 Marick Jan. 4, 1949 2,497,676 Lashells Feb. 14, 1950 2,513,993 Burton July 4, 1950 2,523,353 Boester Sept. 26, 1950 2,563,875 Salton Aug. 14, 1951 2,600,294 Henry June 10, 1952 FOREIGN PATENTS Number Country Date 121,900 Australia Aug. 15, 1946 224,917 Switzerland Mar. 16, 1943 OTHER REFERENCES Miskella, Infra-Red in Industry, published by Miskella Infra-Red 00., Cleveland 4, Ohio, 1947, 64 pages, pages 34, and 63 relied upon. (Copy in Div. 60.) 

